1. Field of the Invention
This invention relates to the field of converting home telephone signals. In particular, the invention relates to converting data contained in telephone signals from an analog format to a digital format.
2. Description of the Related Art
Home telephone systems are typically transmitted to buildings using an analog signal. Connecting computers using telephonic systems requires data transmissions on the telephone lines. The data transmissions are transmitted at bandwidths that are different than voice transmissions. The data transmissions are usually converted from an analog format to a digital format for use with a computing system using digital data.
FIG. 4 illustrates a conversion circuit 400 typically used to convert analog data in telephone lines into a digital signal for use with computing systems. The system includes an amplifier 410 that receives an analog input signal from the telephone line. The amplifier 410 reduces the detection of noise on the telephone line. The comparator 420 receives the signal and compares the signal to an analog threshold. The output from the comparator 420 is a signal having a digital format. The digital signal is signaled to feedback circuit 430. The feedback circuit 430 processes the signal to determine a digital threshold. A digital-analog converter 440 converts the digital threshold to an analog value. The analog value is used by comparator 420 to form the digital signal with the signal received from amplifier 410.
An integrated circuit is provided that samples analog telephone signals. A plurality of shifters store analog values sampled from the telephone signals at discrete time intervals over a duration. A plurality of shifters each carry an analog value for one of the sampled intervals during the duration. Each analog value is propagated through the shifters during the duration. An averager is coupled to the plurality of shifters to determine an average of the analog values carried by the shifters during each interval in the duration. A comparator is coupled to the averager